http://environment.newscientist.com/article/dn12283-corn-biofuel-dangerously-oversold-as-green-energy.html
[Note: check out the interesting links to reports in the original article]
Ethanol fuel made from corn may be being "dangerously oversold" as a
green energy solution according to a new review of biofuels.
The report concludes that the rapidly growing and heavily subsidised
corn ethanol industry in the US will cause significant environmental
damage without significantly reducing the country's dependence on fossil
fuels.
"There are smarter solutions than rushing straight to corn-based
ethanol," says Scott Cullen of the Network for New Energy Choices (NNEC)
and a co-author of the study. "It's just one piece of a more complex
puzzle."
The report analyses hundreds of previous studies, and was compiled by
the environmental advocacy groups Food and Water Watch, NNEC and the
Vermont Law School Institute for Energy and the Environment. The study
was released as the US Congress debates key agriculture and energy laws
that will determine biofuel policy for years to come.
Rapid growth
Of the country's entire corn crop for 2007, 27% is earmarked for
biofuels. That figure is up from 20% in 2006 and is beginning to put a
squeeze on corn for food production.
Yet, even if all corn grown in the US was used for fuel, it would only
offset 15% of the country's gasoline use, according to the study. The
same reduction could be achieved by a 3.5-mile-per-gallon increase in
fuel efficiency standards for all cars and light trucks, according a
federal figures cited in the report.
And using corn-derived ethanol does not necessarily even reduce
greenhouse gas emissions. A number of recent studies have attempted to
assess the total carbon footprint – from the field to the tailpipe – of
the biofuel. Conclusions vary widely from being worse than gasoline to
being about the same.
The report includes a recent study by the US Department of Energy (PDF),
concluding that corn ethanol could reduce greenhouse gas emissions by
18% to 28%.
The same study, however, also notes that cellulosic ethanol could reduce
emissions by 87% compared to gasoline. Cellulosic ethanol produces fuel
from non-food sources such as prairie grasses and woody plants, but
production is still under development.
'Dead zones'
Further concerns are contained in a recent study from the World
Resources Institute (PDF), cited in the report. It says the development
of a corn-based ethanol market would only exacerbate problems already
associated with large-scale corn production.
Such problems include groundwater depletion, soil erosion, algae blooms,
and the formation of "dead zones" in waterways inundated with pesticide
and fertilizer runoff.
"Corn-based ethanol hasn't been pursued because this is the best
solution, it's been because this has been what's been pushed the
hardest," Cullen says. The recent survey notes that Archer Daniels
Midland, the largest US ethanol producer, received $10 billion in
federal subsidies between 1980 and 1997.
But Brian Jennings, of the trade group, the American Coalition for
Ethanol, disagrees. "We can release papers until we are blue in the face
about what is theoretically going to be the best alternative to reduce
our dependence on fossil fuels and to reduce carbon emissions," he says.
"But, from a practical standpoint, we have to start somewhere, and
corn-based ethanol is the most viable alternative fuel on the planet today."
The current Farm Bill, which provides $16.5 billion in federal
agricultural subsidies each year, will expire in September 2007.
Proposals for a new Farm Bill are likely to include significant
subsidies for the continued development of both corn-based ethanol and
cellulosic ethanol.
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Check for earlier Pacific Biofuel posts: http://pacbiofuel.blogspot.com/
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